<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>

    var obj = {
        age: 18,
        getAge: function () {
            console.log(this);

            function fn() {
                console.log(this)
            }

            return fn();
        }
    }
    console.log(obj.getAge());
</script>
</body>
</html>